Developer vaporizing and distributing means for dry developing machines



Aprll 4, 1950 F. o. TRUMP 2,503,225

DEVELOPER VAPORIZING AND DISTRIBUTING MEANS FOR DRY DEVELOPING MACHINES Original Filed Sept. 28, 1945 l 9 0 H ggg Q a (qs .52

; O Q LL .9 g2! k LL i @8 0 i Q &, w

0 \m 9 N v -;N

L O 2 PO a \m L1 w INVENTOR. Fredeiick O. Trump .WIZ zfX MZEQ A TTOR/VE) Patented Apr. 4, 1950 DEVELOPER VAPORIZING AND DISTRIBUT- ING MEANS FOR DRY DEVELOPING MA- CHINES Frederick Otto Trump, Binghamton, N. Y., as-

signor to General Aniline & Film Corporation,

New York, N. Y., a corporation of Delaware Original application September 28, 1945, Serial No. 619,109. Divided and this application September 18, 1947, Serial No.

2 Claims. 1

This application pertains to an invention in so-called dry developing machines, and more specifically, to improvements therein for vaporizing the liquid employed for development so that a more even distribution of vapor over the entire developing surface is obtained. The case is a division of application Serial No. 619,109, filed September 28, 1945, now Patent No. 2,475,165 of July 5, 1949.

It is an object of the invention to provide a system in which the developing liquid fed to the vaporizing chamber may be distributed into a plurality of separate trays or channels wherein precisely the same amount of developer will be delivered and vaporized in each channel and wherein the distribution of the developer and its vaporization are so correlated as evenly to distribute the vapors throughout the vaporizing chamber and developing surface thereof.

In machines of the type described as evidenced in Patents Nos. 2,200,996 and 2,350,257, developing liquid, e. g. an aqueous solution of ammonia, is fed to a developing chamber which has one of its sides perforated or otherwise provided for passage of the developing vapors to the sensitized printing material. Heretofore, the developer has been fed into the vaporizing chamber through a tube which has emptied into a tray inclined in one direction so that the liquid in running from one end to the opposite becomes vaporized by heat applied thereto. As can be seen the rate of flow which varies for different speeds of operation may be such that little liquid reaches the low end of the tray or that so much is fed that some liquid reaches that end without being vaporized. Either situation is an undesired one and leads to unequal vapor distribution and, thus, uneven development.

According to one other system a liquid delivery tube is emptied into a tray at its center and the liquid is caused to flow in both directions since the tray inclines from the center outwardly. This system has not proven satisfactory since it is practically impossible to split the stream equally at the center of the tray.

According to the invention herein described and claimed, the feeding of the developer is first into separate receiving means and are thereafter maintained absolutely separate. Each stream is conveyed to the space within the vaporizing chamber by a tube and is then discharged into an inclined tray, the trays for each stream being inclined in opposite directions.

The actual form of the trays may vary and one preferred type and a modification will be more specifically described in the following disclosure.

In the figures of drawing:

Fig. 1 is a section through a machine of the type to which the invention has been applied.

Fig. 2 is a section through parts of the machine of Fig. 1, this section being taken to show the disposal of the trays and developer conveying means longitudinally of the developer chamber.

Fig. 3 is a plan view of a preferred form of vaporizing tray.

Fig. 4 is an elevation, a of a modified tray.

Now referring to Fig. 1, a part of a dry developing machine is shown which has an enclosing structure It in which is supported a develpart being broken away,

- oping or vaporizing chamber or tank It. This tank has an inclined side H in which there are a plurality of perforations I3 (only a few perforations being shown here) through which the developing (ammonia) vapors may pass to reach the sensitized surface of a sheet of exposed sensitized material l4 which is moved along the perforated surface of the tank by a sealing sleeve or belt I5. This sleeve is moved at a predetermined rate as it is guided about the rollers [6, etc., one of which is positively driven. The sleeve I5 is made from fabric impregnated with rubber or a rubber-like material resistant to the action of the developing vapors.

Within the tank I l and adjacent the lower part thereof is a vaporizing tray ll having running parallel to and close to the developer retaining channels therein, heater elements l8 and [9, not shown in Figs. 1 and 2, but illustrated more clearly in Fig. 3. The heater elements are preferably hollow rods enclosing heater coils which are conveniently connected to a source of current outside the chamber H.

At one side of the chamber II is a developer conveying or pumping means which is of such design as to deliver two separate stream 01' liquid each of which is substantially equal in volume to the other. While this invention is broadly devoted to an improvement in which any liquid pump or delivery means having the abovementioned delivery characteristics will suffice, one preferred form as herein shown is dependent upon a conveying system of buckets at opposite sides of a traveling chain.

A liquid tight casing has therein a quantity of ammonia or other developer 21, the level of which may be maintained by any suitable replenishment. In this casing are two sprockets 22 and 23, one of which is positively driven in timed relation to the driving of the other machine parts, e. g., the roller H3. A conveyor chain 24 passes about these sprockets and has a plurality of buckets 25 attached thereto. There are an equal number of buckets at either side of the chain, only a few being shown here.

The disposal of these buckets is such that they dip into the developer supply 2| and elevate the liquid until the chain passes over the top sprocket at which the buckets are dumped into reservoirs 26 and 21. Reservoir 26 serves to receive the liquid discharged from all those buckets at one side of chain 24 while reservoir 2'! receives an equal amount of developer from the buckets at the opposite side of thechain.

To regulate the actual rate of discharge to the reservoirs and, thus, delivery to the channels in the vaporizing tray, a supplemental and preliminary bucket tipping means is provided which empties an equal and predetermined quantity, less than the whole, contained in the buckets before they reach the sprocket 22. That liquid is merely returned to supply 2!. While it is not necessary to show or to describe in detail all features of the liquid delivery means in this case, reference is made to the parent case, of which this is a division, for a complete and detailed description of those parts.

In Figs. 3 and 4, the details of the evaporating tray itself are shown. The tray ll, Fig. 3, is pressed from sheet metal and is so formed as to have two troughs or channels 28 and 29. The tray is mounted with its top surfaces horizontally disposed and thus the diverging channel I! slopes or inclines downwardly so liquid discharged into its upper or shallow end by tube 30 flows toward the opposite end Likewise, developer discharged by tube 3i into channel 29 flows to the right, Fig. 3. i

The opposite 'disposal'of these channels and the delivery to opposite ends makes possible a more even distribution of vapor as the developer flows from one end to the other in each channel. The heater elements afiect each side equally and the defective distribution mentioned in the early paragraphs is virtually eliminated.

Referring to Fig. 4, a modified tray has its center point highest and the ends lower so that the tubes 32 and 33, counterparts of tubes 39 and 3|, discharge at opposite sides of the center 34 of the oppositely directed and downwardly inclined channels 35 and 36.

Obviously, the modification of Fig. 4 may be reversed so that the ends are elevated and the center then constitutes a low or discharge point for excess liquid. The tubes then feed to the high ends so that the flow is toward the center.

While one embodiment of the invention has been disclosed, it is to be understood that the inventive concept may be carried out in a number of ways. This application is, therefore, not to be limited to the precise details described, but is intended to cover all variations and modifications thereof falling within the spirit of the invention and the scope of the claims.

Iclaim:

1. In a developing machine of the type described the combination of a vaporizing tank, a vaporizing tray within said tank, said tray having two separate portions for the reception of liquid to be vaporized, said portions being inclined in opposite directions and means for feeding developing liquid in equal quantities to each oppositely directed inclined part of the vaporizing tray.

2. Mechanism as defined in claim 1 wherein said tray comprises two oppositely directed, inclined liquid containing portions, each being inclined downwardly from a highest point at substantially the center of the tray.

FREDERICK OTTO TRUMP.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,325,559 Eckelmann Dec. 23, 1919 1,568,660 Dumas Jan. 5, 1926 1,813,834 Ballard et a1 July 7, 1931 1,932,406 Harris Oct. 31, 1933 2,284,414 Gamon May 26, 1942 2,384,155 Brunk Sept. 4, 1945 

